package com.wangxiaotao.springcloud.lb;

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * 自定义轮询算法
 * @author Wangxiaotao
 * @create 2021-09-08-16:07
 */
@Component
public class MyIb implements LoadBalancer{

    private AtomicInteger atomicInteger=new AtomicInteger(0);

    public final int getAndIncrement(){
        int current;
        int next;
        do {
            current = this.atomicInteger.get();
            next = current >= 2147483647 ? 0 : current + 1;
        }while (!this.atomicInteger.compareAndSet(current,next));
        System.out.println("*****next："+next);
        return next;
    }

    public ServiceInstance instance(List<ServiceInstance> serviceInstances) {
        int index=getAndIncrement() % serviceInstances.size();
        return serviceInstances.get(index);
    }
}
